The present invention relates to a golf club shaft and to a golf club having the same.
Golf club shafts have a flexural rigidity distribution over the entire length from the tip end to the butt end that is designed to hit a longer ball. For example, according to Japanese Patent Application Publication No. 9-234256, a flexural rigidity distribution is designed so that the flexural rigidity is higher in a middle part between a point 300 mm from the tip end and a point 300 mm from the butt end. Such a flexural rigidity distribution helps to keep the axis of the shaft substantially straight during a swing, thus facilitating accurately recovering of the position of the club face at the time of addressing, so that the flying distance increases, and the directional accuracy improves.
In addition, according to Japanese Patent Application Publication No. 2002-177423, the rate of change of the flexural rigidity in a section H having a length of 100 to 450 mm within a range from a point 0 mm to a point 450 mm from the butt end of the shaft is one to five times as high as the rate of change of the flexural rigidity in a section M having a length of 200 to 500 mm within a range from a point 400 mm to a point 900 mm from the butt end of the shaft. In the section M, the flexural rigidity slowly increases from the tip end toward the butt end. Thus, the section M provides sufficient flexure and restoring force and thus contributes to increasing the flying distance. In the section H, the rate of change of the flexural rigidity is higher than in the section M to provide higher flexural rigidity. Thus, the section H contributes to providing firm grip feeling and high directional stability.